Analysis of the Devonian Shale in Analysis of the Devonian Shale in Kentucky for Potential COKentucky for Potential CO22

Sequestration and Enhanced Sequestration and Enhanced Natural Gas ProductionNatural Gas Production

Brandon C. Nuttall, James A. Drahovzal, Brandon C. Nuttall, James A. Drahovzal, Cortland F. Eble, R. Marc BustinCortland F. Eble, R. Marc Bustin

KentuckyGeological SurveyU N I V E R S I T Y O F K E N T U C K Y

U.S. DOE/NETL DE-FC26-02NT41442U.S. DOE/NETL DE-FC26-02NT41442

Basic Research: Basic Research: FeasibilityFeasibility

• COCO22 sorption sorption

capacitycapacity

• CHCH44 displacement displacement

potentialpotential

Why Black Shales?Why Black Shales?

• Distribution and potential Distribution and potential storage volumestorage volume

• Known producerKnown producer– Gas adsorbed on kerogen and clayGas adsorbed on kerogen and clay

• Analogous to CBM?Analogous to CBM?

Black Shale DistributionBlack Shale Distribution

Modified from Ettensohn, 1998, Compressional Tectonic Controls...Modified from Ettensohn, 1998, Compressional Tectonic Controls...in Schieber and others, eds., Shales and Mudstones Iin Schieber and others, eds., Shales and Mudstones I

AntrimAntrim

BakkenBakken

ChattanoogaChattanooga

ExshawExshaw

New AlbanyNew Albany

OhioOhio

Shale NomenclatureShale Nomenclature

New AlbanyNew Albany

ChattanoogaChattanooga

OhioOhio

Hamilton-Smith, 1993, Gas Exploration in the Devonian ShalesHamilton-Smith, 1993, Gas Exploration in the Devonian Shalesof Kentucky: KGS, Ser 10, Bul. 4.of Kentucky: KGS, Ser 10, Bul. 4.

Geologic Geologic ColumnColumn

Surface

1,000’

2,000’

3,000’

4,000’

Coal measures, Coal measures, mixed sand, shale, mixed sand, shale,

and coal.and coal.

““Salt” sandsSalt” sands

SSand and shaleand and shale

CCarbonatearbonate

Pen

nsy

lvan

ian

Pen

nsy

lvan

ian

Mis

siss

ipp

ian

Mis

siss

ipp

ian

Dev

on

ian

Dev

on

ian

SSand and shaleand and shale

Carbonaceous Carbonaceous black shaleblack shale

3,800’ +/- of mixed 3,800’ +/- of mixed sand, shale, and sand, shale, and carbonate provide carbonate provide adequate adequate reservoir seal.reservoir seal.

Composite thickness data from Knott and Leslie County wells and Dillman and Ettensohn (1980)

Devonian Shale Devonian Shale Type Log, Eastern Type Log, Eastern

KentuckyKentucky

Lower Huron is Lower Huron is thought to have the thought to have the most sequestration most sequestration potential.potential.

Up

per

par

tL

ow

er

par

t

Devonian Shale in KentuckyDevonian Shale in Kentucky

Estimated gas in place:Estimated gas in place:63 to 112 tcf63 to 112 tcf

Present in subsurfacePresent in subsurface>=1000’ deep and >=100’ thick>=1000’ deep and >=100’ thickProducing areaProducing area

Big Sandy Reservoir InfoBig Sandy Reservoir Info

• Completion interval >500’Completion interval >500’

• Average porosity 4.3%Average porosity 4.3%

• Max. porosity 11%Max. porosity 11%

• Temperature 84Temperature 84ooFF

• Average pressure 400 psiAverage pressure 400 psi

• Permeability <0.1 mdPermeability <0.1 mdAtlas of Major Appalachian Gas Plays, 1996

Classic Production DeclineClassic Production Decline

0

30

60

1950 1960 1970 1980 1990

Mill

ion

Cu

bic

Fee

t

39494

Cum: 471 MMcf26 years

Eastern Kentucky Devonian Shale Gas Production

Production Incline Suggests Production Incline Suggests Adsorbed GasAdsorbed Gas

0

10

20

30

1940 1950 1960 1970 1980 1990

Mill

ion

Cu

bic

Fee

t

40625

Cum: 379 MMcf40 years

Eastern Kentucky Devonian Shale Gas Production

Project Year 1Project Year 1

• KGS Well Sample LibraryKGS Well Sample Library– Identified drill cuttingsIdentified drill cuttings

– PetrologyPetrology

– Sorption isothermsSorption isotherms

– Identified optimum shale faciesIdentified optimum shale facies

Sampling CriteriaSampling Criteria

• Minimize sample alterationsMinimize sample alterations– Recent wellsRecent wells

– Unwashed samplesUnwashed samples

• Geophysical logs availableGeophysical logs available

• Distributed over shale gas Distributed over shale gas producing areaproducing area

Sample locations

Average Organic ContentAverage Organic Content

2.1%

7.0%3.7% 2.7%

0%

5%

10%

15%

20%

25%

30%

Zielinski &McIver, 1982

Ettensohn,1998

This study, asreceived

This study,acid washed

Tot

al O

rgan

ic C

arb

on

Average TOCAverage TOC

0% 1% 2% 3% 4%

Devonian Shale(lower part)

Lower Huron

Devonian Shale(upper part)

Mean Random ReflectanceMean Random Reflectance

Upper oil window and Upper oil window and wet gas/condensateswet gas/condensates

R0 random x 1.066 ~ R0 max

0%

10%

20%

30%

40%

50%F

req

uenc

y

1 1.25 1.5 1.75

R0 random

0.5 1.0 1.25 1.5 1.75

Adsorbed GasAdsorbed Gas

0 20 40 60 80

Devonian Shale(lower part)

Lower Huron

Devonian Shale(upper part)

Standard cubic feet per ton

CO2CH4

Adsorption IsothermsAdsorption Isotherms

0

25

50

75

100

0 200 400 600 800 1000

PSIA

CO

2 ad

sorb

ed (

SC

F/t

on)

Ohio Shale (Undif)Upper OhioLower HuronLower Ohio

Calculated Langmuir VolumesCalculated Langmuir Volumes

0

20

40

60

80

200 300 400 500 600

Pressure (psia)

Ohio Shale (Undif)Upper OhioLower HuronLower Ohio

CO

2 ad

sorb

ed (

SC

F/t

on)

Project Year 2Project Year 2

• Cooperative access to new wellCooperative access to new well– Sidewall coreSidewall core

– ECS logging suiteECS logging suite

– PetrologyPetrology

– COCO22 sorption/CH sorption/CH44 displacement displacement

CNR 24752 Elk HornCNR 24752 Elk Horn

ClevelandCleveland

Three LickThree Lick

Upper HuronUpper Huron

Middle HuronMiddle Huron

Lower HuronLower Huron

OlentangyOlentangy

SunburySunburyBordenBorden

BereaBerea

11

44

11

11

11

22

Sidewall CoresSidewall Coresfor CHfor CH44

DisplacementDisplacement

ECS LogECS Log

**

*

*

Lower Huron

Si Ca Fe S Ti Gd

* Sidewall core Sidewall core

sample locations in sample locations in the Lower Huronthe Lower Huron

Work Plan: Year 3Work Plan: Year 3

• Reporting and technology Reporting and technology transfertransfer– Finish long-term sorption analysesFinish long-term sorption analyses

– Implement Web data interfaceImplement Web data interface

– Final reportFinal report

Typical Reservoir ConditionsTypical Reservoir Conditionsfor COfor CO22 Injection Injection

0

200

400

600

800

1000

1200

-100 -75 -50 -25 0 25 50 75 100

Temp (oF)

Pre

ssur

e (p

sia)

Sol

id

Liquid

Gas

CriticalPoint

Saturation Line

Mel

ting

Lin

e

27.6 Billion Tons CO27.6 Billion Tons CO2 2 EstimatedEstimated

40 scf/ton thickness weighted average

>3 MM

<1 MM

Tons/sq kmTons/sq km

Future ResearchFuture Research

• Demonstration projectDemonstration project– COCO22 monitoring monitoring

• Surface soils• Produced gas

– Reservoir simulationReservoir simulation

ConclusionConclusion

The organic-rich Mississippian–The organic-rich Mississippian–Devonian shales of Kentucky Devonian shales of Kentucky have the potential to sequester have the potential to sequester large volumes of COlarge volumes of CO22..

www.uky.edu/kgs